Method and apparatus for downlink data buffering considering cross carrier scheduling in a wireless communication system

ABSTRACT

Methods and apparatuses for downlink data buffering considering cross carrier scheduling in a wireless communication system are disclosed herein. In one method, the UE receives configuration of a first serving cell and a second serving cell from a network. The UE receives and/or monitors a first PDCCH transmitted on a scheduling CORESET of the second serving cell, wherein the first PDCCH schedules a first PDSCH transmitted on the first serving cell. The UE receives and/or monitors a second PDCCH transmitted on a scheduling CORESET of the second serving cell, wherein the second PDCCH schedules a second PDSCH transmitted on the second serving cell. The UE receives and/or buffers the second PDSCH via a TCI state used for PDCCH quasi co-location indication of the CORESET with the lowest CORESET-ID in the latest slot in which one or more CORESETs are configured for the UE, before the UE decodes successfully the second PDCCH. The UE does not receive and/or buffer the first PDSCH before the UE decodes successfully the first PDCCH.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 16/364,065, filed Mar. 25, 2019, which claims priority to andthe benefit of U.S. Provisional Patent Application Ser. No. 62/648,194,filed on Mar. 26, 2018, with the entire disclosures of theseapplications fully incorporated herein by reference.

FIELD

This disclosure generally relates to wireless communication networks,and more particularly, to a method and apparatus for downlink databuffering considering cross carrier scheduling in a wirelesscommunication system.

BACKGROUND

With the rapid rise in demand for communication of large amounts of datato and from mobile communication devices, traditional mobile voicecommunication networks are evolving into networks that communicate withInternet Protocol (IP) data packets. Such IP data packet communicationcan provide users of mobile communication devices with voice over IP,multimedia, multicast and on-demand communication services.

An exemplary network structure is an Evolved Universal Terrestrial RadioAccess Network (E-UTRAN). The E-UTRAN system can provide high datathroughput in order to realize the above-noted voice over IP andmultimedia services. A new radio technology for the next generation(e.g., 5G) is currently being discussed by the 3GPP standardsorganization. Accordingly, changes to the current body of 3GPP standardare currently being submitted and considered to evolve and finalize the3GPP standard.

SUMMARY

Methods and apparatuses for downlink data buffering considering crosscarrier scheduling in a wireless communication system are disclosedherein. In one method, the UE receives a configuration of a firstserving cell and a second serving cell from a network. The UE receivesand/or monitors a first PDCCH transmitted on a scheduling CORESET of thesecond serving cell, wherein the first PDCCH schedules a first PDSCHtransmitted on the first serving cell. The UE receives and/or monitors asecond PDCCH transmitted on a scheduling CORESET of the second servingcell, wherein the second PDCCH schedules a second PDSCH transmitted onthe second serving cell. The UE receives and/or buffers the second PDSCHvia a TCI state used for PDCCH quasi co-location indication of theCORESET with the lowest CORESET-ID in the latest slot in which one ormore CORESETs are configured for the UE, before the UE decodessuccessfully the second PDCCH. The UE does not receive and/or buffer thefirst PDSCH before the UE decodes successfully the first PDCCH.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram of a wireless communication system according toone exemplary embodiment.

FIG. 2 is a block diagram of a transmitter system (also known as accessnetwork) and a receiver system (also known as user equipment or UE)according to one exemplary embodiment.

FIG. 3 is a functional block diagram of a communication system accordingto one exemplary embodiment.

FIG. 4 is a functional block diagram of the program code of FIG. 3according to one exemplary embodiment.

FIG. 5 is a reproduction of Table 7.3.2.1-1 taken from 3GPP 3GPPR1-1721341.

FIG. 6 is a flow diagram for one exemplary embodiment from theperspective of a User Equipment (UE).

FIG. 7 is a flow diagram for one exemplary embodiment from theperspective of a network.

DETAILED DESCRIPTION

The exemplary wireless communication systems and devices described belowemploy a wireless communication system, supporting a broadcast service.Wireless communication systems are widely deployed to provide varioustypes of communication such as voice, data, and so on. These systems maybe based on code division multiple access (CDMA), time division multipleaccess (TDMA), orthogonal frequency division multiple access (OFDMA),3GPP LTE (Long Term Evolution) wireless access, 3GPP LTE-A orLTE-Advanced (Long Term Evolution Advanced), 3GPP2 UMB (Ultra MobileBroadband), WiMax, 3GPP NR (New Radio) wireless access for 5G, or someother modulation techniques.

In particular, the exemplary wireless communication systems devicesdescribed below may be designed to support one or more standards such asthe standard offered by a consortium named “3rd Generation PartnershipProject” referred to herein as 3GPP, including: R1-1801292, 3GPP TS38.212 V15.0.1 (2018-02) 3rd Generation Partnership Project, TechnicalSpecification Group Radio Access Network, NR, Multiplexing and channelcoding (Release 15); R1-1801294, 3GPP TS 38.214 V15.0.0 (2018-02) 3rdGeneration Partnership Project, Technical Specification Group RadioAccess Network, NR, Physical layer procedures for data (Release 15);Final Report of 3GPP TSG RAN WG1 #85 v1.0.0; Final Report of 3GPP TSGRAN WG1 #86 v1.0.0; Final Report of 3GPP TSG RAN WG1 #86bis v1.0.0;Final Report of 3GPP TSG RAN WG1 #87 v1.0.0; Final Report of 3GPP TSGRAN WG1 #AH1_NR v1.0.0; Final Report of 3GPP TSG RAN WG1 #88 v1.0.0;Final Report of 3GPP TSG RAN WG1 #88bis v1.0.0; Final Report of 3GPP TSGRAN WG1 #89 v1.0.0; Final Report of 3GPP TSG RAN WG1 #AH_NR3 v1.0.0;Final Report of 3GPP TSG RAN WG1 #90bis v1.0.0; Final Chairman's Note of3GPP TSG RAN WG1 Meeting #91; Final Report of 3GPP TSG RAN WG1 #AH_1801v1.0.0; and Draft Report of 3GPP TSG RAN WG1 #92 v0.2.0. The standardsand documents listed above are hereby expressly incorporated byreference in their entirety.

FIG. 1 shows a multiple access wireless communication system accordingto one embodiment of the invention. An access network 100 (AN) includesmultiple antenna groups, one including 104 and 106, another including108 and 110, and an additional including 112 and 114. In FIG. 1, onlytwo antennas are shown for each antenna group, however, more or fewerantennas may be utilized for each antenna group. Access terminal 116(AT) is in communication with antennas 112 and 114, where antennas 112and 114 transmit information to access terminal 116 over forward link120 and receive information from access terminal 116 over reverse link118. Access terminal (AT) 122 is in communication with antennas 106 and108, where antennas 106 and 108 transmit information to access terminal(AT) 122 over forward link 126 and receive information from accessterminal (AT) 122 over reverse link 124. In a FDD system, communicationlinks 118, 120, 124 and 126 may use different frequency forcommunication. For example, forward link 120 may use a differentfrequency then that used by reverse link 118.

Each group of antennas and/or the area in which they are designed tocommunicate is often referred to as a sector of the access network. Inthe embodiment, antenna groups each are designed to communicate toaccess terminals in a sector of the areas covered by access network 100.

In communication over forward links 120 and 126, the transmittingantennas of access network 100 may utilize beamforming in order toimprove the signal-to-noise ratio of forward links for the differentaccess terminals 116 and 122. Also, an access network using beamformingto transmit to access terminals scattered randomly through its coveragecauses less interference to access terminals in neighboring cells thanan access network transmitting through a single antenna to all itsaccess terminals.

An access network (AN) may be a fixed station or base station used forcommunicating with the terminals and may also be referred to as anaccess point, a Node B, a base station, an enhanced base station, anevolved Node B (eNB), a network node, a network, or some otherterminology. An access terminal (AT) may also be called user equipment(UE), a wireless communication device, terminal, access terminal or someother terminology.

FIG. 2 is a simplified block diagram of an embodiment of a transmittersystem 210 (also known as the access network) and a receiver system 250(also known as access terminal (AT) or user equipment (UE) in a MIMOsystem 200. At the transmitter system 210, traffic data for a number ofdata streams is provided from a data source 212 to a transmit (TX) dataprocessor 214.

In one embodiment, each data stream is transmitted over a respectivetransmit antenna. TX data processor 214 formats, codes, and interleavesthe traffic data for each data stream based on a particular codingscheme selected for that data stream to provide coded data.

The coded data for each data stream may be multiplexed with pilot datausing OFDM techniques. The pilot data is typically a known data patternthat is processed in a known manner and may be used at the receiversystem to estimate the channel response. The multiplexed pilot and codeddata for each data stream is then modulated (i.e., symbol mapped) basedon a particular modulation scheme (e.g., BPSK, QPSK, M-PSK, or M-QAM)selected for that data stream to provide modulation symbols. The datarate, coding, and modulation for each data stream may be determined byinstructions performed by processor 230.

The modulation symbols for all data streams are then provided to a TXMIMO processor 220, which may further process the modulation symbols(e.g., for OFDM). TX MIMO processor 220 then provides N_(T) modulationsymbol streams to N_(T) transmitters (TMTR) 222 a through 222 t. Incertain embodiments, TX MIMO processor 220 applies beamforming weightsto the symbols of the data streams and to the antenna from which thesymbol is being transmitted.

Each transmitter 222 receives and processes a respective symbol streamto provide one or more analog signals, and further conditions (e.g.,amplifies, filters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MIMO channel. N_(T)modulated signals from transmitters 222 a through 222 t are thentransmitted from N_(T) antennas 224 a through 224 t, respectively.

At receiver system 250, the transmitted modulated signals are receivedby N_(R) antennas 252 a through 252 r and the received signal from eachantenna 252 is provided to a respective receiver (RCVR) 254 a through254 r. Each receiver 254 conditions (e.g., filters, amplifies, and downconverts) a respective received signal, digitizes the conditioned signalto provide samples, and further processes the samples to provide acorresponding “received” symbol stream.

An RX data processor 260 then receives and processes the N_(R) receivedsymbol streams from N_(R) receivers 254 based on a particular receiverprocessing technique to provide N_(T) “detected” symbol streams. The RXdata processor 260 then demodulates, deinterleaves, and decodes eachdetected symbol stream to recover the traffic data for the data stream.The processing by RX data processor 260 is complementary to thatperformed by TX MIMO processor 220 and TX data processor 214 attransmitter system 210.

A processor 270 periodically determines which pre-coding matrix to use(discussed below). Processor 270 formulates a reverse link messagecomprising a matrix index portion and a rank value portion.

The reverse link message may comprise various types of informationregarding the communication link and/or the received data stream. Thereverse link message is then processed by a TX data processor 238, whichalso receives traffic data for a number of data streams from a datasource 236, modulated by a modulator 280, conditioned by transmitters254 a through 254 r, and transmitted back to transmitter system 210.

At transmitter system 210, the modulated signals from receiver system250 are received by antennas 224, conditioned by receivers 222,demodulated by a demodulator 240, and processed by a RX data processor242 to extract the reserve link message transmitted by the receiversystem 250. Processor 230 then determines which pre-coding matrix to usefor determining the beamforming weights then processes the extractedmessage.

Turning to FIG. 3, this figure shows an alternative simplifiedfunctional block diagram of a communication device according to oneembodiment of the invention. As shown in FIG. 3, the communicationdevice 300 in a wireless communication system can be utilized forrealizing the UEs (or ATs) 116 and 122 in FIG. 1 or the base station (orAN) 100 in FIG. 1, and the wireless communications system is preferablythe LTE system or the NR system. The communication device 300 mayinclude an input device 302, an output device 304, a control circuit306, a central processing unit (CPU) 308, a memory 310, a program code312, and a transceiver 314. The control circuit 306 executes the programcode 312 in the memory 310 through the CPU 308, thereby controlling anoperation of the communications device 300. The communications device300 can receive signals input by a user through the input device 302,such as a keyboard or keypad, and can output images and sounds throughthe output device 304, such as a monitor or speakers. The transceiver314 is used to receive and transmit wireless signals, deliveringreceived signals to the control circuit 306, and outputting signalsgenerated by the control circuit 306 wirelessly. The communicationdevice 300 in a wireless communication system can also be utilized forrealizing the AN 100 in FIG. 1.

FIG. 4 is a simplified block diagram of the program code 312 shown inFIG. 3 in accordance with one embodiment of the invention. In thisembodiment, the program code 312 includes an application layer 400, aLayer 3 portion 402, and a Layer 2 portion 404, and is coupled to aLayer 1 portion 406. The Layer 3 portion 402 generally performs radioresource control. The Layer 2 portion 404 generally performs linkcontrol. The Layer 1 portion 406 generally performs physicalconnections.

Some descriptions of a downlink control information (DCI) format of asignal transmitted on a Physical Downlink Control Channel (PDCCH) asdisclosed in 3GPP R1-1801292 3GPP TS 38.212 V15.0.1 are quoted below:

7.3.1 DCI Formats

The DCI formats defined in table 7.3.1-1 are supported.

FIG. 5 (a reproduction of Table 7.3.1-1 taken from 3GPP R1-1801292).

7.3.1.2 DCI Formats for Scheduling of PDSCH 7.3.1 0.2.1 Format 1_0

DCI format 1_0 is used for the scheduling of PDSCH in one DL cell.The following information is transmitted by means of the DCI format 1_0with CRC scrambled by C-RNTI:

-   -   Identifier for DCI formats—[1] bits    -   Frequency domain resource assignment −┌log₂(N_(RB)        ^(DL,BWP)(N_(RB) ^(DL,BWP)+1)/2)┐ bits        -   N_(RB) ^(DL,BWP) is the size of the initial bandwidth part            in case DCI format 1_0 is monitored in the common search            space in CORESET 0        -   N_(RB) ^(DL,BWP) is the size of the active bandwidth part            otherwise    -   Time domain resource assignment—X bits as defined in Subclause        5.1.2.1 of [6, TS38.214]    -   VRB-to-PRB mapping—1 bit    -   Modulation and coding scheme—5 bits as defined in Subclause        5.1.3 of [6, TS38.214]    -   New data indicator—1 bit    -   Redundancy version—2 bits as defined in Table 7.3.1.1.1-2    -   HARQ process number—4 bits    -   Downlink assignment index—2 bits as defined in Subclause 9.1.3        of [5, TS38.213], as counter DAI    -   TPC command for scheduled PUCCH—[2] bits as defined in Subclause        7.2.1 of [5, TS38.213]    -   PUCCH resource indicator—[2] bits as defined in Subclause 9.2.3        of [5, TS38.213]    -   PDSCH-to-HARQ_feedback timing indicator—[3] bits as defined in        Subclause x.x of [5, TS38.213]        The following information is transmitted by means of the DCI        format 1_0 with CRC scrambled by P-RNTI:    -   Short Messages Indicator—1 bit. This bit is used to indicate        whether the short message only or scheduling information only is        carried in the Paging DCI.        The following information is transmitted by means of the DCI        format 1_0 with CRC scrambled by SI-RNTI:    -   XXX—x bit        The following information is transmitted by means of the DCI        format 1_0 with CRC scrambled by RA-RNTI:    -   XXX—x bit        The following information is transmitted by means of the DCI        format 1_0 with CRC scrambled by CS-RNTI:    -   XXX—x bit        If the number of information bits in format 1_0 prior to padding        is less than the payload size of format 0_0 for scheduling the        same serving cell, zeros shall be appended to format 1_0 until        the payload size equals that of format 0_0.

7.3.1.2.2 Format 1_1

DCI format 1_1 is used for the scheduling of PDSCH in one cell.The following information is transmitted by means of the DCI format 1_1with CRC scrambled by C-RNTI:

-   -   Carrier indicator—0 or 3 bits as defined in Subclause x.x of [5,        TS38.213].

< . . . >

-   -   Time domain resource assignment—0, 1, 2, 3, or 4 bits as defined        in Subclause 5.1.2.1 of [6, TS38.214]. The bitwidth for this        field is determined as ┌log₂(I)┐ bits, where I is the number of        rows in the higher layer parameter [pdsch-symbolAllocation].

< . . . >

-   -   Transmission configuration indication—0 bit if higher layer        parameter tci-PresentInDCI is not enabled; otherwise 3 bits as        defined in Subclause x.x of [6, TS38.214].

Some descriptions of a Downlink (DL) resource assignment are disclosedin 3GPP R1-1801294 3GPP TS 38.214 V15.0.0 as quoted below:

5.1.2.1 Resource Allocation in Time Domain

When the UE is scheduled to receive PDSCH by a DCI, the Time domainresource assignment field of the DCI provides a row index of an RRCconfigured table pdsch-symbolAllocation, where the indexed row definesthe slot offset K₀, the start and length indicator SLIV, and the PDSCHmapping type to be assumed in the PDSCH reception. Given the parametervalues of the indexed row:

-   -   The slot allocated for the PDSCH is

${\left\lfloor {n \cdot \frac{2^{\mu_{PDSCH}}}{2^{\mu \; {PDCCH}}}} \right\rfloor + K_{0}},$

where n is the slot with the scheduling DCI, and K₀ is based on thenumerology of PDSCH, and

-   -   The starting symbol S relative to the start of the slot, and the        number of consecutive symbols L counting from the symbol S        allocated for the PDSCH are determined from the start and length        indicator SLIV:        -   if (L−1)≤7 then            -   SLIV=14·(L−1)+S        -   else            -   SLIV=14·(14−L+1)+(14−1−S)        -   where 0<L≤14−S, and    -   The PDSCH mapping type is set to Type A or Type B as defined in        sub-clause 7.4.1.1.2 of [4, TS 38.211].        The UE shall consider the S and L combinations satisfying the        following conditions as valid PDSCH allocations:    -   For PDSCH mapping type A: S∈{0,1,2,3}, L∈{[X], . . . , 14}    -   For PDSCH mapping type B: S∈{0, . . . , 12}, L∈{2,4,7}    -   The UE is not expected to receive any TB across slot boundaries        determined by the numerology associated with the PDSCH        transmission.        When the UE is configured with aggregationFactorDL>1, the UE may        expect that the TB is repeated within each symbol allocation        among each of the aggregationFactorDL consecutive slots and the        PDSCH is limited to a single transmission layer.        If the UE procedure for determining slot configuration as        defined in Subclause 11.1 of [6, TS 38.213] determines symbol of        a slot allocated for PDSCH as uplink symbols, the transmission        on that slot is omitted for multi-slot PDSCH transmission.

As disclosed in 3GPP TSG RAN WG1 #86 v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management:

R1-168468 Definitions supporting beam related procedures Nokia,Qualcomm, CATT, Intel, NTT DoCoMo, Mediatek, Ericsson, ASB, Samsung, LGE{  • Beam management = a set of L1/L2 procedures to acquire and maintaina set of TRP(s) and/or UE beams that can be used for DL and ULtransmission/reception, which include at least following aspects:  ∘Beam determination = for TRP(s) or UE to select of its own Tx/Rxbeam(s).  ∘ Beam measurement = for TRP(s) or UE to measurecharacteristics of received beamformed signals  ∘ Beam reporting = forUE to report information a property/quality of of beamformed signal(s)based on beam measurement  ∘ Beam sweeping = operation of covering aspatial area, with beams transmitted and/or received during a timeinterval in a predetermined way. }

As disclosed in 3GPP TSG RAN WG1 #86bis v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management inRANI:

R1-1610825 WF on Beam Management CATT, CATR, CMCC, Xinwei

Agreements:

-   -   For downlink, NR supports beam management with and without        beam-related indication        -   When beam-related indication is provided, information            pertaining to UE-side beamforming/receiving procedure used            for data reception can be indicated through QCL to UE

As disclosed in 3GPP TSG RAN WG1 #87 v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management:

R1-1613670 WF on Beam Management for Control and Data Channel ZTE, ZTEMicroelectronics, ASTRI, Intel, Samsung, LGE Agreements:

-   -   NR supports with and without a downlink indication to derive QCL        assumption for assisting UE-side beamforming for downlink        control channel reception

As disclosed in 3GPP TSG RAN WG1 #AH1_NR v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management:

R1-1701506 WF on Beam Indication Samsung, Ericsson, KT Corp., Verizon,NTT DOCOMO, AT&T, LGE Agreements:

-   -   For reception of DL control channel, support indication of        spatial QCL assumption between an DL RS antenna port(s), and DL        RS antenna port(s) for demodulation of DL control channel        -   Note: Indication may not be needed for some cases:    -   For reception of DL data channel, support indication of spatial        QCL assumption between DL RS antenna port(s) and DMRS antenna        port(s) of DL data channel        -   Different set of DMRS antenna port(s) for the DL data            channel can be indicated as QCL with different set of RS            antenna port(s)        -   Option 1: Information indicating the RS antenna port(s) is            indicated via DCI        -   Option 2: Information indicating the RS antenna port(s) is            indicated via MAC-CE, and will be assumed until the next            indication        -   Option 3: Information indicating the RS antenna port(s) is            indicated via a combination of MAC CE and DCI        -   At least one option is supported        -   Note: Indication may not be needed for some cases:

As disclosed in 3GPP TSG RAN WG1 #88 v.1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management inRANI:

R1-1703958 WF on Beam Indication Samsung, KT Corp., NTT DOCOMO, Verizon,Intel, CATT, Ericsson, Huawei, HiSilicon Agreements:

-   -   For reception of unicast DL data channel, support indication of        spatial QCL assumption between DL RS antenna port(s) and DMRS        antenna port(s) of DL data channel: Information indicating the        RS antenna port(s) is indicated via DCI (downlink grants)        -   The information indicates the RS antenna port(s) which is            QCL-ed with DMRS antenna port(s)        -   Note: related signalling is UE-specific

As disclosed in 3GPP TSG RAN WG1 #89 v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management:

R1-1709496 Potential Agreements on Beam Management Qualcomm Agreements:

-   -   Support spatial QCL assumption between antenna port(s) within a        CSI-RS resource(s) and antenna port of an SS Block (or SS block        time index) of a cell        -   The other QCL parameters not precluded        -   Note: default assumption may be no QCL    -   Configuration of QCL for UE specific NR-PDCCH is by RRC and        MAC-CE signalling        -   Note that MAC-CE is not always needed        -   Note: For example, DL RS QCLed with DMRS of PDCCH for delay            spread, Doppler spread, Doppler shift, and average delay            parameters, spatial parameters

As disclosed in 3GPP TSG RAN WG1 #AH_NR3 v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management:

R1-1716842 WF on QCL Indication for DL Physical Channels Ericsson, CATT,NTT Docomo, Samsung, Qualcomm Agreement:

A UE is RRC configured with a list of up to M candidate TransmissionConfiguration Indication (TCI) states at least for the purposes of QCLindication

-   -   Each TCI state can be configured with one RS Set    -   Each ID (FFS: details of ID) of DL RS at least for the purpose        of spatial QCL in an RS Set can refer to one of the following DL        RS types:        -   SSB        -   Periodic CSI-RS        -   Aperiodic CSI-RS        -   Semi-persistent CSI-RS

Agreement:

The QCL configuration for PDCCH contains the information which providesa reference to a TCI state

-   -   Note: The indication of QCL configuration is done by RRC or        RRC+MAC CE

R1-1716890 Summary on Beam Management Offline Qualcomm Agreement:

-   -   For QCL indication for PDSCH:        -   When TCI states are used for QCL indication, the UE receives            an N-bit TCI field in DCI            -   The UE assumes that the PDSCH DMRS is QCL with the DL                RS(s) in the RS Set corresponding to the signaled TCI                state    -   FFS: Timing between when the UE receives a QCL        configuration/indication and the first time that the QCL        assumption may be applied for demodulation of PDSCH or PDCCH

As disclosed in 3GPP TSG RAN WG1 #90bis v1.0.0 (Final Report), thefollowing quotations describe some agreements on beam management:

R1-1718920 Beam Management Offline Discussion Summary QualcommAgreement:

Support at least the explicit approach for the update of spatial QCLreference in a TCI state.

-   -   Note: In the explicit approach, the TCI state is updated using        either RRC or RRC+MAC-CE based approach    -   Note: In the implicit approach, when a set of aperiodic CSI-RS        resources are triggered, the triggering DCI includes a TCI state        index which provides spatial QCL reference for the triggered set        of CSI-RS resources. Following the measurement, the spatial QCL        reference in the RS set corresponding to the indicated TCI state        is updated based on the preferred CSI-RS determined by the UE.        Other operations of implicit approaches are not precluded.        R1-1719059 WF on Beam Management Samsung, CATT, Huawei,        HiSilicon, NTT Docomo, MediaTek, Intel, OPPO, SpreadTrum, AT&T,        InterDigital, CHTTL, KDDI, LG Electronics, Sony, China Unicom,        Ericsson, VIVO, China Telecom, Qualcomm, National Instruments,        Vodafone        Also supported by Verizon

Agreement:

-   -   Proposal: Update the association of TCI state and DL RS        -   Initialization/Update of the ID of a DL RS(s) in the RS Set            used at least for spatial QCL purposes is done at least via            explicit signalling Support the following methods for the            explicit signalling:            -   RRC            -   RRC+MAC-CE    -   Proposal: Presence of TCI in DCI    -   For the case when at least spatial QCL is configured/indicated,        support higher-layer UE-specific configuration of whether or not        TCI field is present in DL-related DCI        -   Not present: No dynamic indication of QCL parameters for            PDSCH is provided in DL-related DCI            -   For PDSCH, UE applies higher-layer signalling of QCL                parameters/indication for determining QCL parameters                except for the case of beam management without                beam-related indication (ref:Annex) where no spatial QCL                parameters are higher layer configured        -   Present: Details on next proposal.        -   Proposed candidate solutions should consider            -   Below and above 6 GHz DL beam related operation with and                without beam indication            -   Downlink beam management with and without beam                indication (ref Annex)    -   Note: this proposal does not apply to the case of beam        management without beam-related indication (ref: Annex)    -   Proposal: Timing issue of beam indication for PDSCH    -   For the case when at least spatial QCL is configured/indicated,        NR supports the beam indication for PDSCH as follows, if TCI        field is present:        -   The TCI field is always present in the associated DCI for            PDSCH scheduling irrespective of same-slot scheduling or            cross-slot scheduling.        -   If the scheduling offset <threshold K: PDSCH uses a            pre-configured/pre-defined/rule-based spatial assumption            -   Threshold K can be based on UE capability only if                multiple candidate values of K are supported.        -   If the scheduling offset >=threshold K: PDSCH uses the beam            (spatial QCL parameter) indicated by the N-bit TCI field in            the assignment DCI.    -   Note: this proposal does not apply to the case of beam        management without beam-related indication        }

Agreements:

-   -   Support parameter Is-TCI-Present        -   Whether for the case when at least spatial QCL is            configured/indicated, if TCI field is present or not present            in DL-related DCI.        -   Boolean        -   Default is True    -   For the case when TCI is not present in DL-related DCI, continue        discussion of the details regarding higher-layer signaling of        QCL parameters/indication for determining QCL parameters for        PDSCH    -   NR supports a mechanism to identify the spatial QCL if the        offset between the time of reception of DL assignment for the        PDSCH and time of reception of PDSCH is less than        Threshold-Sched-Offset.    -   NR does not support the RRC parameter in beam management:        Threshold-Sched-Offset.        -   FFS if such a parameter is included as a UE capability

As disclosed in 3GPP TSG RAN WG1 Meeting #91 (Final Chairman's Note),the following quotations describe some agreements on beam management:

R1-1721396 Summary of Beam Mgmt Open Issues Qualcomm Agreement:

-   -   The state Is-TCI-Present is configured on a per-CORESET basis    -   For beam management with beam indication, on all CORESETs        configured with Is-TCI-Present=false, the TCI state used for        PDCCH is reused for PDSCH reception

Agreement:

-   -   A candidate set of DL RSs are configured using RRC mechanism        -   Each state of M TCI states is RRC configured with a downlink            RS set used as a QCL reference, and            -   MAC-CE is used to select up to TN TCI states out of M                for PDSCH QCL indication                -   The same set of M TCI states are reused for CORESET                -   K TCI states are configured per CORESET                -   When K>1, MAC CE can indicate which one TCI state to                    use for control channel QCL indication                -   When K=1, no additional MAC CE signaling is                    necessary

R1-1721640 Summary of Beam Mgmt Qualcomm Agreement:

-   -   When the scheduling offset is <=k, the PDSCH uses QCL assumption        that is based on a default TCI state (e.g. the first state of        the TN states used for PDSCH QCL indication)

Agreement

Between initial RRC configuration and MAC CE activation of TCI states,the UE may assume that both PDCCH and PDSCH DMRS are spatially QCL-edwith the SSB determined during initial access

R1-1721696 Summary of Beam Mgmt Qualcomm Agreement:

-   -   When the scheduling offset is <=k, and the PDSCH uses QCL        assumption that is based on a default TCI state        -   The default TCI state corresponds to the TCI state used for            control channel QCL indication for the lowest CORESET ID in            that slot

The following terminology and assumptions may be used hereinafter.

-   -   BS: a network central unit or a network node in NR which is used        to control one or multiple TRPs which are associated with one or        multiple cells. Communication between BS and TRP(s) is via        fronthaul. BS may be referred to as central unit (CU), eNB, gNB,        or NodeB.    -   TRP: a transmission and reception point provides network        coverage and directly communicates with UEs. TRP may be referred        to as distributed unit (DU) or network node.    -   Cell: a cell is composed of one or multiple associated TRPs,        i.e. coverage of the cell is composed of coverage of all        associated TRP(s). One cell is controlled by one BS. Cell may be        referred to as TRP group (TRPG).    -   Serving beam: serving beam for a UE is a beam generated by a        network node, e.g. TRP, which is configured to be used to        communicate with the UE, e.g. for transmission and/or reception.    -   Candidate beam: candidate beam for a UE is a candidate of a        serving beam. Serving beam may or may not be candidate beam.

When a UE receives a Physical Downlink Shared Channel (PDSCH), the UEmay determine the antenna port quasi co-location for PDSCH receptionaccording to the Transmission Configuration Indication (TCI) field inthe scheduling Physical Downlink Control Channel (PDCCH). As describedin 3GPP TSG RAN WG1 #87 v1.0.0 (Final Report), if the TCI-PresentInDCIis set as ‘Disabled’ for the Control Resource Set (CORESET) schedulingthe PDSCH or the PDSCH is scheduled by a DCI format 1_0, for determiningPDSCH antenna port quasi co-location, the UE assumes that the TCI statefor the PDSCH is identical to the TCI state applied to the CORESET usedfor the PDCCH transmission. If the TCI-PresentinDCI is set as ‘Enabled’,the UE shall use the TCI-States according to the value of the‘Transmission Configuration Indication’ field in the detected PhysicalDownlink Control Channel (PDCCH) with the Downlink Control Information(DCI) for determining the antenna port quasi co-location for PDSCHreception.

The UE may assume that the antenna ports of one Demodulation ReferenceSignal (DM-RS) port group of the PDSCH of a serving cell are quasico-located with the Reference Signal(s) (RS(s)) in the RS set withrespect to the Quasi Co-location (QCL) type parameter(s) given by theindicated TCI state if the time offset between the reception of the DLDCI and the corresponding PDSCH is equal to or greater than a thresholdThreshold-Sched-Offset, where the threshold is related to the UEcapability. For both the cases when TCI-PresentInDCI=‘Enabled’ andTCI-PresentInDCI=‘Disabled’, if the offset between the reception of theDownlink (DL) DCI and the corresponding PDSCH is less than the thresholdThreshold-Sched-Offset, the UE may assume that the antenna ports of oneDM-RS port group of the PDSCH of a serving cell are quasi co-locatedbased on the TCI state used for the PDCCH quasi co-location indicationof the lowest CORESET-ID in the latest slot in which one or moreCORESETs are configured for the UE.

In other words, before the UE decodes a scheduling PDCCH (successfully),the UE receives and/or buffers the scheduled PDSCH via using the TCIstate or spatial parameter or beam for receiving the CORESET with thelowest identification (ID) in the latest slot in which one or moreCORESETs are configured for the UE, e.g., the CORESET with the lowestidentification (ID) monitored in the latest slot in which one or moreCORESETs are monitored by the UE. However, for the cross carrierscheduling case, the story may be different.

For cross carrier scheduling case, the CORESET configuration of ascheduled serving cell and a scheduling serving cell can be categorizedinto at least the following cases.

Case 1: the network does not configure the CORESET configuration for thescheduled serving cell. In other words, the network prevents from or isnot allowed to configure the CORESET configuration of the scheduledserving cell. The UE receives and/or monitors the PDCCH for thescheduled serving cell on the CORESETs or the CORESET configuration ofthe scheduling serving cell. For example, a scheduled serving cell isCell 1 and a scheduling serving cell is Cell 2. The PDCCH of Cell 1 istransmitted on the CORESETs of Cell 2, and the UE receives and/ormonitors the PDCCH of Cell 1 on the CORESETs of Cell 2.

Case 2: the network configures the CORESET configuration for a scheduledserving cell. The UE receives and/or monitors the PDCCH for thescheduled serving cell on the CORESETs of the scheduled serving cell. Inone embodiment, the CORESETs of the scheduled serving cell may betransmitted on (the frequency resources of) the scheduling serving cell.In other words, the UE receives and/or monitors the PDCCH for thescheduled serving cell based on the CORESET configuration of thescheduled serving cell. For example, a scheduled serving cell is Cell 1and a scheduling serving cell is Cell 2. The PDCCH of Cell 1 istransmitted on the CORESETs of Cell 1. The UE monitors the PDCCH of Cell1 on the CORESETs of Cell 1. In one embodiment, the CORESETs of Cell 1are transmitted on (the frequency resources of) Cell 2. In oneembodiment, the UE monitors the PDCCH of Cell 1 on the CORESET(s) ofCell 1, wherein the CORESET(s) of Cell 1 is located on the frequencyresources of Cell 2.

For Case 1, the UE receives a scheduling PDCCH transmitted on theCORESET(s) of Cell 2, wherein the scheduling PDCCH schedules a PDSCHtransmitted on Cell 1. Before the UE decodes the scheduling PDCCH onCell 2 (successfully), the UE receives and/or buffers the scheduledPDSCH of Cell 1 via using the TCI state or spatial parameter or beam forreceiving the CORESET of Cell 2 with the lowest CORESET ID in the latestslot in which one or more CORESETs are configured for the UE.

However, the TCI state applied for the CORESET(s) of Cell 2 may not beappropriate for the PDSCH transmitted on Cell 1, at least in cases inwhich Cell 1 and Cell 2 are interband carriers. For example, Cell 1 is acarrier located on frequency band above 6 GHz and Cell 2 is a carrierlocated on frequency band below 6 GHz.

Hence, for a cross carrier scheduling case, at least for Case 1, beforethe scheduling PDCCH is decoded (successfully), how to receive and/orbuffer the PDSCH of the scheduled serving cell needs to be considered ifthe scheduling PDCCH is transmitted on the CORESETs of the schedulingserving cell. That is, how to decide the TCI state (or the spatialparameter or the receiving beam) to receive and/or buffer the PDSCHtransmitted on the scheduled serving cell before the scheduling PDCCH isdecoded (successfully).

For Case 2, the UE receives a PDCCH transmitted on the CORESET(s) ofCell 1, wherein the PDCCH schedules a PDSCH transmitted on Cell 1. Inone embodiment, the CORESETs of Cell 1 are transmitted on the frequencyresources of Cell 2. Although Cell 1 has its own CORESET(s) transmittedon Cell 2, the UE may use the TCI states or spatial parameters or beams,for receiving CORESETs of Cell 2, to receive CORESETs of Cell 1. In oneembodiment, a set of TCI states (TCI-StatesPDCCH), providing quasico-location information for receiving the PDCCH, may or may not beconfigured in the CORESET configuration of Cell 1.

Since the CORESET(s) of Cell 1 is transmitted on (the frequencyresources of) Cell 2, the UE may not be sure which serving cell for theUE as reference when referring to the CORESET with the lowest CORESET IDfor the buffering scheduled PDSCH transmitted on Cell 1. That is, theCORESET with the lowest CORESET ID can be the CORESET with the lowestCORESET ID in Cell 1, Cell 2, or the CORESET with the lowest CORESET IDamong the CORESETs in Cell 1 and Cell 2. Even before the UE decodes ascheduling PDCCH, it is using the TCI state or spatial parameter or beamfor receiving the CORESET with the lowest ID of Cell 1 via which the UEreceives and buffers the scheduled PDSCH, the TCI state or spatialparameter or beam for receiving the CORESET with the lowest ID of Cell 1may not be appropriate.

Since the UE may use the TCI states or spatial parameters or beams,which is for receiving CORESETs of Cell 2, to receive CORESETs of Cell1, it may not be appropriate for the UE to receive the PDSCH in Cell 1by using that for receiving the CORESETs of Cell 2 before the UE decodesa PDCCH. For example, Cell 1 and Cell 2 are interband carriers. Like theissue in Case 1, how to decide the TCI state (or spatial parameter orreceiving beam) to receive and/or buffer the PDSCH transmitted on thescheduled serving cell, before the scheduling PDCCH is decoded(successfully), needs to be considered.

In this specification, the following solutions or embodiments can beused, at least but not limited to, to handle cross carrier schedulingcases or to determine the TCI states or spatial parameters or receivingbeams for receiving the PDSCH of a scheduled serving cell before the UEdecodes a PDCCH.

According to one concept, before a UE decodes a PDCCH successfully in ascheduling serving cell, the UE may not assume that the PDSCH antennaport quasi co-location for receiving the PDSCH in a scheduled servingcell is based on the quasi co-location information for receiving theCORESET with the lowest CORESET-ID, transmitted in the schedulingserving cell, in the latest slot in which one or more CORESETs of thescheduling serving cell are configured for the UE.

In one embodiment, before the UE decodes a PDCCH successfully in ascheduling serving cell, the UE may not assume that the antenna ports ofone DM-RS port group of a PDSCH of a scheduled serving cell are quasico-located based on the TCI state used for PDCCH quasi co-locationindication of the CORESET with the lowest CORESET-ID, transmitted in thescheduling serving cell, in the latest slot in which one or moreCORESETs of the scheduling serving cell are configured for the UE.

In one embodiment, the CORESET with the lowest CORESET-ID may beselected among the CORESETs configured for the scheduling serving cell.

In one embodiment, the CORESET with the lowest CORESET-ID may beselected among the CORESETs configured for the scheduled serving cell.

In one embodiment, the CORESET with the lowest CORESET-ID may beselected among the CORESETs configured for the scheduling serving celland the CORESETs configured for the scheduled serving cell.

In another concept, before a UE decodes a PDCCH successfully in ascheduling serving cell, the UE determines the PDSCH antenna port quasico-location for receiving the PDSCH in a scheduled serving cell based ona higher layer configuration.

In one embodiment, before the UE decodes a PDCCH successfully in ascheduling serving cell, the UE determines the PDSCH antenna port quasico-location for receiving PDSCH in a scheduled serving cell based on anindicator.

In one embodiment, before the UE decodes a PDCCH successfully in ascheduling serving cell, the UE interprets a TCI state applied for theCORESET with the lowest CORESET-ID, transmitted in the schedulingserving cell, based on a higher layer configuration or an indicator.

In one embodiment, before the UE decodes a PDCCH successfully in ascheduling serving cell and for determining the PDSCH antenna port quasico-location for receiving PDSCH in a scheduled serving cell, the UE usesthe TCI state applied to the CORESET with the lowest CORESET-IDtransmitted in the scheduling serving cell.

In another concept, if the network configures a corresponding CORESETconfiguration for scheduled serving cells, the parameter providing quasico-location information for receiving PDCCH (e.g., TCI-StatesPDCCH) mayor may not be configured. This may mean that if the network configures acorresponding CORESET configuration for the scheduled serving cells, theparameter providing the quasi co-location information for receiving thePDCCH (e.g. TCI-StatesPDCCH) is not allowed to be configured.

In one embodiment, if the network configures a corresponding CORESETconfiguration for the scheduled serving cells, the parameter providingthe quasi co-location information for the receiving PDCCH (e.g.TCI-StatesPDCCH) may be ignored or may not be used when the PDCCH ofscheduled serving cell is transmitted on the scheduling serving cell.

In one embodiment, if the network configures a corresponding CORESETconfiguration for the scheduled serving cells, the TCI-StatesPDCCH inthe CORESETs of the scheduled serving cell is not configured.

In one embodiment, if the network configures a corresponding CORESETconfiguration for the scheduled serving cells, the TCI-StatesPDCCH inthe CORESETs of the scheduled serving cell is ignored or not used by aUE when the UE receives or monitors the PDCCH of the scheduled servingcell on the scheduling serving cell.

In one embodiment, if the network configures a corresponding CORESETconfiguration for the scheduled serving cells, the UE uses the TCIstates or spatial parameters or receiving beams, for receiving theCORESETs of the scheduling serving cell, to receive the CORESETs of thescheduled serving cell.

In one embodiment, if network configures a corresponding CORESETconfiguration for scheduled serving cells, TCI-StatesPDCCH in CORESETsof scheduled serving cell comprises a set of TCI states, wherein the setof TCI states are associated with the reference signals transmitted inthe scheduling serving cell.

In one embodiment, if the network configures a corresponding CORESETconfiguration for the scheduled serving cells, the UE interprets the RSindices in the TCI-StatesPDCCH in the CORESETs of the scheduled servingcell by associating those with the reference signals transmitted in thescheduling serving cell.

In another concept, if the UE receives a PDSCH in a serving cell,wherein a scheduling PDCCH, which schedules the PDSCH, is transmitted onanother serving cell, the UE may expect the time offset between thereception of the DCI of the scheduling PDCCH and the PDSCH to be greaterthan or equal to a threshold.

In one embodiment, if the UE receives a PDSCH in a serving cell, whereina scheduling PDCCH, which schedules the PDSCH, is transmitted on anotherserving cell, the UE may not expect the time offset between thereception of the DCI of the scheduling PDCCH and the PDSCH to be lessthan the threshold.

In one embodiment, for both the cases when TCI-PresentInDCI isconfigured as ‘Enabled’ and when TCI-PresentInDCI is configured as‘Disabled’ or not configured, if the UE receives a PDSCH in a servingcell, wherein a scheduling PDCCH, which schedules the PDSCH, istransmitted on another serving cell, the UE may not expect the timeoffset between the reception of the DCI of the scheduling PDCCH and thePDSCH to be less than the threshold.

In one embodiment, if the UE receives a PDSCH in a serving cell, whereina scheduling PDCCH, which schedules the PDSCH, is transmitted on anotherserving cell, and if the time offset between the reception of the DCI ofthe scheduling PDCCH and the PDSCH is less than the threshold, the UEdoes not receive and/or decode the PDSCH in the serving cell or theremaining PDSCH in the serving cell.

In one embodiment, if the UE receives a PDSCH in a serving cell, whereina scheduling PDCCH, which schedules the PDSCH, is transmitted on anotherserving cell, and if the time offset between the reception of the DCI ofthe scheduling PDCCH and the PDSCH is less than the threshold, the UEdiscards the PDSCH in the serving cell or discards the remaining PDSCHin the serving cell.

In one embodiment, if the UE receives a PDSCH in a serving cell, whereina scheduling PDCCH, which schedules the PDSCH, is transmitted on anotherserving cell, and if the time offset between the reception of the DCI ofthe scheduling PDCCH and the PDSCH is less than the threshold, the UEdetects or considers the scheduling PDCCH is an inconsistent controlinformation.

In one embodiment, if the UE receives a PDSCH in a serving cell, whereina scheduling PDCCH, which schedules the PDSCH, is transmitted on anotherserving cell, and if the time offset between the reception of the DCI ofthe scheduling PDCCH and the PDSCH is less than the threshold, the UEdoes not transmit an acknowledgement signal, which corresponds to thePDSCH in the serving cell, to network, e.g. ACK/NACK.

Notably, the above-disclosed embodiments or concepts can be applied forboth the cases when TCI-PresentInDCI is configured as ‘Enabled’ and whenTCI-PresentInDCI is configured as ‘Disabled’ or not configured. Forexample, when TCI-PresentInDCI is configured as ‘Enabled’ and whenTCI-PresentInDCI is configured as ‘Disabled’ or not configured, if theUE receives a PDSCH in a serving cell, wherein a scheduling PDCCH, whichschedules the PDSCH, is transmitted on another serving cell, and if thetime offset between the reception of the DCI of the scheduling PDCCH andthe PDSCH is less than the threshold, the UE does not transmit anacknowledgement signal, which corresponds to the PDSCH in the servingcell, to network, e.g. ACK/NACK.

In some instances, the threshold is related to the time duration neededfor the UE to decode a PDCCH successfully.

In some instances, the threshold is related to UE capability.

In some instances, the threshold can be Threshold-Sched-Offset.

The above-disclosed concepts can be applied to at least (but not limitedto) the following embodiments.

In one embodiment, a UE is configured with a first serving cell and asecond serving cell. The control signal of the first serving cell istransmitted on the second serving cell, e.g., PDCCH scheduling PDSCH.The downlink data transmission of the first serving cell is transmittedon the first serving cell. The UE receives or monitors a first PDCCHtransmitted on a scheduling CORESET of the second serving cell. A firstPDSCH is transmitted on the first serving cell. In one instance, thefirst PDCCH may schedule the first PDSCH.

In one example, the UE receives or monitors a second PDCCH transmittedon the scheduling CORESET. In one instance, a second PDSCH istransmitted on the second serving cell. The second PDCCH may schedulethe second PDSCH.

In some instances, a reference CORESET is a CORESET with the lowestCORESET-ID in the latest slot in which one or more CORESETs areconfigured for the UE.

In some instances, the reference CORESET is transmitted on the secondserving cell.

In some instances, the reference CORESET may be a CORESET configured forthe second serving cell.

In some instances, the reference CORESET may be a CORESET configured forthe first serving cell.

In some instances, the reference CORESET may be a CORESET with thelowest CORESET-ID among CORESETs configured for the first serving celland the CORESETs configured for the second serving cell.

Before the UE decodes the second PDCCH successfully, the UE may assumethat the PDSCH antenna port quasi co-location for receiving the secondPDSCH is based on the quasi co-location information for receiving thereference CORESET.

Alternatively, before the UE decodes the first PDCCH successfully, theUE may assume that the PDSCH antenna port quasi co-location forreceiving the first PDSCH is not based on the quasi co-locationinformation for receiving the reference CORESET.

Alternatively, before the UE decodes the first PDCCH successfully, theUE may determine the PDSCH antenna port quasi co-location based on a TCIstate not for receiving the reference CORESET, wherein the PDSCH antennaport quasi co-location is for receiving the first PDSCH in a scheduledserving cell.

The following alternatives are provided for determining the TCI stateapplied for the first PDSCH, or for determining PDSCH antenna port quasico-location, before the UE decodes the first PDCCH successfully.

One alternative is as the follows: before a UE decodes the first PDCCHsuccessfully, the UE determines the PDSCH antenna port quasi co-locationfor receiving the first PDSCH based on a default TCI state.

In one embodiment, before a UE decodes the first PDCCH successfully, theUE receives the first PDSCH via the PDSCH antenna port quasi co-locationderived from the default TCI state.

In one embodiment, the UE may assume that the antenna ports of one DM-RSport group of the first PDSCH are quasi co-located with the RS(s) in theRS set with respect to the QCL type parameter(s) given by the indicatedTCI state if the time offset between the reception of the DL DCI of thefirst PDCCH and the first PDSCH is equal to or greater than a thresholdThreshold-Sched-Offset, where the threshold is based on UE capability.

In one embodiment, for both the cases when TCI-PresentInDCI=‘Enabled’and when TCI-PresentInDCI=‘Disabled’ or not configured, if the offsetbetween the reception of the Downlink Control Information (DCI) of thefirst PDCCH and the first PDSCH is less than the thresholdThreshold-Sched-Offset, the UE may assume that the antenna ports of oneDM-RS port group of the first PDSCH are quasi co-located based on thedefault TCI state.

In one embodiment, the default TCI state is one of TCI states in theactivated TCI states for receiving PDSCH in the first serving cell.

Additionally or alternatively, the default TCI state is a TCI statemapped to one of codeponints in the TCI field for receiving PDSCH in thefirst serving cell.

Additionally or alternatively, the default TCI state is the TCI statewith the lowest TCI state ID in the activated TCI states for receivingPDSCH in the first serving cell.

Additionally or alternatively, the default TCI state is a TCI statemapped to codepoint 0 in the TCI field for receiving PDSCH in the firstserving cell.

Additionally or alternatively, the default TCI state is the TCI stateapplied for receiving at least one of CORESETs configured for the firstserving cell and/or the second serving cell.

Additionally or alternatively, the default TCI state is the TCI stateapplied for receiving the CORESET with the lowest CORESET ID among theCORESETs configured for the first serving cell and/or the second servingcell.

Another alternative is as follows: at least the TCI state applied forreceiving the reference CORESET is at least associated with an index ofthe reference signal transmitted in the first serving cell andcorresponding QCL type.

Additionally or alternatively, at least the TCI state applied forreceiving the reference CORESET is at least associated with the index ofa first reference signal and the index of a second reference signal andthe corresponding QCL types. The first reference signal is transmittedon the first serving cell and the second reference signal is transmittedon the second serving cell.

Before the UE decodes the second PDCCH successfully, the UE assumes thatthe TCI state for receiving the second PDSCH is identical to the TCIstate applied for the reference CORESET; the UE refers to the index ofthe second reference signal and the corresponding QCL type wheninterpreting the TCI state. In one instance, the UE receives the secondPDSCH via PDSCH antenna port quasi co-location derived from the index ofthe second reference signal and the corresponding QCL type in a TCIstate applied to receiving the reference CORESET.

Before the UE decodes the first PDCCH successfully, the UE assumes thatthe TCI state for receiving the first PDSCH is identical to the TCIstate applied to the reference CORESET; the UE refers to the index ofthe first reference signal and the corresponding QCL type wheninterpreting the TCI state. In one embodiment, the UE receives the firstPDSCH via PDSCH antenna port quasi co-location derived from the index ofthe first reference signal and the corresponding QCL type in a TCI stateapplied to receiving the reference CORESET.

In one embodiment, the UE may assume that the antenna ports of one DM-RSport group of the first PDSCH are quasi co-located with the RS(s) in theRS set with respect to the QCL type parameter(s) given by the indicatedTCI state if the time offset between the reception of the DL DCI of thefirst PDCCH and the first PDSCH is equal to or greater than a thresholdThreshold-Sched-Offset, wherein the threshold is based on UE capability.

In one embodiment, for the cases when TCI-PresentInDCI=‘Enabled’ andwhen TCI-PresentInDCI=‘Disabled’ or not configured, if the offsetbetween the reception of the DL DCI of the second PDCCH and the secondPDSCH is less than the threshold, Threshold-Sched-Offset, the UE mayassume that the antenna ports of one DM-RS port group of the secondPDSCH are quasi co-located with the second reference signal(s) in the RSset with respect to the QCL type parameter(s) used for the referenceCORESET.

In one embodiment, for the cases when TCI-PresentInDCI=‘Enabled’ andwhen TCI-PresentInDCI=‘Disabled’ or not configured, if the offsetbetween the reception of the DL DCI of the first PDCCH and the firstPDSCH is less than the threshold, Threshold-Sched-Offset, the UE mayassume that the antenna ports of one DM-RS port group of the first PDSCHare quasi co-located with the first reference signal(s) in the RS setwith respect to the QCL type parameter(s) used for the referenceCORESET.

In one embodiment, the association, between the TCI state applied toreceiving the reference CORESET and the first reference signal, isconfigured in the configuration of the first serving cell, e.g., theconfiguration related to cross carrier scheduling,CrossCarrierSchedulingConfig.

In one embodiment, the association, between the TCI state applied forreceiving the reference CORESET and the first reference signal, isconfigured in the configuration of the second serving cell, e.g., theCORESET configuration of the second serving cell.

Another alternative is as follows: before the UE decodes the first PDCCHsuccessfully, the UE assumes that the TCI state for receiving the firstPDSCH is identical to the TCI state applied to the reference CORESET.

In some exemplary embodiments, the TCI state applied for receiving thereference COREET is associated with index of reference signalstransmitted on the second serving cell and corresponding QCL types.

In some exemplary embodiments, before the UE decodes the first PDCCHsuccessfully, the UE receives the first PDSCH via PDSCH antenna portquasi co-location derived from an index of a first reference signaltransmitted in the first serving cell and the corresponding QCL type.

In some exemplary embodiments, the first reference signal is associatedwith the second reference signal.

In some exemplary embodiments, the first reference signal is derivedfrom the second reference signal.

In some exemplary embodiments, the association between the firstreference signal and the second reference signal is (explicitly)configured to the UE.

In some exemplary embodiments, the association between the firstreference signal and the second reference signal is specified to the UE,e.g., specified in the specification.

In some exemplary embodiments, the association between the firstreference signal and the second reference signal is (implicitly) derivedby the UE.

In some exemplary embodiments, the association between the firstreference signal and the second reference signal is (implicitly) derivedby the UE via a rule, e.g., a mapping between the index of the firstreference signal and the index of the second reference signal.

In some exemplary embodiments, the UE may assume that the antenna portsof one DM-RS port group of the first PDSCH are quasi co-located with theRS(s) in the RS set with respect to the QCL type parameter(s) given bythe indicated TCI state if the time offset between the reception of theDL DCI of the first PDCCH and the first PDSCH is equal to or greaterthan a threshold, Threshold-Sched-Offset, wherein the threshold is basedon UE capability.

In some exemplary embodiments, for the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, if the offset between the reception of the DL DCI of thesecond PDCCH and the second PDSCH is less than the threshold,Threshold-Sched-Offset, the UE may assume that the antenna ports of oneDM-RS port group of the second PDSCH are quasi co-located with thesecond reference signal(s) in the RS set with respect to the QCL typeparameter(s) used for the reference CORESET.

In some exemplary embodiments, for the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, if the offset between the reception of the DL DCI of thefirst PDCCH and the first PDSCH is less than the threshold,Threshold-Sched-Offset, the UE may assume that the antenna ports of oneDM-RS port group of the first PDSCH are quasi co-located with a firstreference signal(s), wherein the first reference signal(s) is associatedwith the second reference signal(s) in the RS set with respect to theQCL type parameter(s) used for the reference CORESET.

In another embodiment, a UE is configured with a first serving cell anda second serving cell. The control signal of the first serving cell istransmitted on the second serving cell, e.g., PDCCH scheduling PDSCH.The downlink data transmission of the first serving cell is transmittedon the first serving cell. The UE receives or monitors a first PDCCHtransmitted on a scheduling CORESET of the second serving cell. A firstPDSCH is transmitted on the first serving cell. In one example, thefirst PDCCH may schedule the first PDSCH.

In one embodiment, the UE receives or monitors a second PDCCHtransmitted on the scheduling CORESET. In one embodiment, a second PDSCHis transmitted on the second serving cell. The second PDCCH may schedulethe second PDSCH.

In one exemplary embodiment, a reference CORESET is a CORESET with thelowest CORESET-ID in the latest slot in which one or more CORESETs areconfigured for the UE.

In one exemplary embodiment, the reference CORESET is transmitted on thesecond serving cell.

In one exemplary embodiment, the reference CORESET may be a CORESETconfigured for the second serving cell.

Additionally or alternatively, the reference CORESET may be a CORESETconfigured for the first serving cell.

Additionally or alternatively, the reference CORESET may be a CORESETwith the lowest CORESET-ID among CORESETs configured for the firstserving cell and the CORESETs configured for the second serving cell.

In one exemplary embodiment, before the UE decodes the second PDCCHsuccessfully, the UE may assume that the PDSCH antenna port quasico-location for receiving the second PDSCH is based on the quasico-location information for receiving the reference CORESET.

In one exemplary embodiment, before the UE decodes the first PDCCHsuccessfully, the UE may determine the PDSCH antenna port quasico-location for receiving the first PDSCH based on a higher layerconfiguration.

In one exemplary embodiment, before the UE decodes the first PDCCHsuccessfully, the UE may determine the PDSCH antenna port quasico-location for receiving the first PDSCH based on an indicator.

The following alternatives are provided for determining the TCI stateapplied to the first PDSCH, or for determining PDSCH antenna port quasico-location, or before the UE decodes the first PDCCH successfully.

An alternate is as the followings. Before the UE decodes the first PDCCHsuccessfully, the UE assumes that the TCI state for receiving the firstPDSCH is identical to a default TCI state.

In one exemplary embodiment, before the UE decodes the first PDCCHsuccessfully, the UE receives the first PDSCH via the PDSCH antenna portquasi co-location derived from the default TCI state.

In one exemplary embodiment, the default TCI state is based on anindicator.

In one exemplary embodiment, if the indicator indicates ‘1’ or ‘True’ or‘Enabled’, the default TCI state is identical to a TCI state forreceiving the reference CORESET.

In one exemplary embodiment, if the indicator indicates ‘0’ or ‘False or‘Disabled’, the default TCI state is identical to a TCI state not forreceiving the reference CORESET.

In one exemplary embodiment, if the indicator indicates ‘0’ or ‘False or‘Disabled’, the default TCI state is one of the TCI states in theactivated TCI states for receiving PDSCH in the first serving cell.

Additionally or alternatively, if the indicator indicates ‘0’ or ‘Falseor ‘Disabled’, the default TCI state is a TCI state mapped to one ofcodepoints in the TCI field for receiving PDSCH in the first servingcell.

Additionally or alternatively, if the indicator indicates ‘0’ or ‘Falseor ‘Disabled’, the default TCI state is the TCI state with the lowestTCI state ID in the activated TCI states for receiving PDSCH in thefirst serving cell.

Additionally or alternatively, if the indicator indicates ‘0’ or ‘Falseor ‘Disabled’, the default TCI state is a TCI state mapped to codepoint0 in the TCI field for receiving PDSCH in the first serving cell.

Additionally or alternatively, if the indicator indicates ‘0’ or ‘Falseor ‘Disabled’, the default TCI state is the TCI state applied toreceiving at least one of the CORESETs configured for the first servingcell and/or the second serving cell.

Additionally or alternatively, if the indicator indicates ‘0’ or ‘Falseor ‘Disabled’, the default TCI state is the TCI state applied toreceiving the CORESET with the lowest CORESET ID among the CORESETsconfigured for the first serving cell and/or the second serving cell.

Alternatively or additionally, the opposite result from the value of theindicator is not precluded.

Alternatively or additionally, regardless of the value of the indicator,before the UE decodes the second PDCCH successfully, the UE assumes thatthe TCI state for receiving the second PDSCH is identical to a TCI statefor receiving the reference CORESET.

In one exemplary embodiment, the UE may assume that the antenna ports ofone DM-RS port group of the first PDSCH are quasi co-located with theRS(s) in the RS set with respect to the QCL-type parameter(s) given bythe indicated TCI state if the time offset between the reception of theDL DCI of the first PDCCH and the first PDSCH is equal to or greaterthan a threshold, Threshold-Sched-Offset, wherein the threshold is basedon UE capability.

In one exemplary embodiment, for the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, if the offset between the reception of the DL DCI of thefirst PDCCH and the first PDSCH is less than the threshold,Threshold-Sched-Offset, according to the value of the indicator, the UEmay assume that the antenna ports of one DM-RS port group of the firstPDSCH are quasi co-located based on the default state.

Another alternative is as follows: at least the TCI state applied to forreceiving the reference CORESET is at least associated with an index ofthe reference signal transmitted in the first serving cell and thecorresponding QCL-type.

Additionally or alternatively, at least the TCI state applied toreceiving the reference CORESET is at least associated with the index ofa first reference signal, the index of a second reference signal, andthe corresponding QCL-types. The first reference signal is transmittedon the first serving cell and the second reference signal is transmittedon the second serving cell.

In one exemplary embodiment, if the indicator indicates ‘1’ or ‘True’ or‘Enabled’, before the UE decodes the first PDCCH successfully, the UEassumes that the TCI state for receiving the first PDSCH is identical tothe TCI state applied to receiving the reference CORESET; the UE refersto the index of the first reference signal and the corresponding QCLtype when interpreting the TCI state for receiving the referenceCORESET; in one example, the UE receives the first PDSCH via PDSCHantenna port quasi co-location derived from the index of the firstreference signal and the corresponding QCL type in a TCI state appliedto receiving the reference CORESET.

In one exemplary embodiment, if the indicator indicates ‘0’ or ‘False’or ‘Disabled’, before the UE decodes the first PDCCH successfully, theUE assumes that the TCI state for receiving the first PDSCH is identicalto the TCI state applied to receiving the reference CORESET; the UErefers to the index of the second reference signal and the correspondingQCL type when interpreting the TCI state for receiving the referenceCORESET; in one exemplary embodiment, the UE receives the first PDSCHvia PDSCH antenna port quasi co-location derived from the index of thesecond reference signal and the corresponding QCL type in a TCI stateapplied to receiving the reference CORESET.

In one exemplary embodiment, the opposite result from the value of theindicator is not precluded.

In one exemplary embodiment, regardless of the value of the indicator,before the UE decodes the second PDCCH successfully, the UE assumes thatthe TCI state for receiving the second PDSCH is identical to the TCIstate applied for receiving the reference CORESET; the UE refers to theindex of the second reference signal and the corresponding QCL type wheninterpreting the TCI state regardless of the value of the indicator. Inone exemplary embodiment, the UE receives the first PDSCH via PDSCHantenna port quasi co-location derived from the index of the secondreference signal and the corresponding QCL type in a TCI state appliedfor receiving the reference CORESET.

In one exemplary embodiment, the association between the TCI stateapplied to the reference CORESET and the first reference signal isconfigured in the configuration of the first serving cell, e.g., theconfiguration related to cross carrier scheduling,CrossCarrierSchedulingConfig.

In one exemplary embodiment, the association between the TCI stateapplied for the reference CORESET and the first reference signal isconfigured in the configuration of the second serving cell, e.g. theCORESET configuration of the second serving cell.

In one exemplary embodiment, the UE may assume that the antenna ports ofone DM-RS port group of the first PDSCH are quasi co-located with theRS(s) in the RS set with respect to the QCL-type parameter(s) given bythe indicated TCI state if the time offset between the reception of theDL DCI of the first PDCCH and the first PDSCH is equal to or greaterthan a threshold, Threshold-Sched-Offset, wherein the threshold is basedon UE capability.

In one exemplary embodiment, for the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, according to the value of the indicator, and if the offsetbetween the reception of the DL DCI of the second PDCCH and the secondPDSCH is less than the threshold, Threshold-Sched-Offset, the UE mayassume that the antenna ports of one DM-RS port group of the secondPDSCH are quasi co-located with the second reference signal(s) in the RSset with respect to the QCL-type parameter(s) used for the referenceCORESET.

In one exemplary embodiment, for the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, according to the value of the indicator, and if the offsetbetween the reception of the DL DCI of the first PDCCH and the firstPDSCH is less than the threshold Threshold-Sched-Offset, the UE mayassume that the antenna ports of one DM-RS port group of the first PDSCHare quasi co-located with the first reference signal(s) in the RS setwith respect to the QCL-type parameter(s) used for the referenceCORESET.

Another alternative is as follows: if the indicator indicates ‘1’ or‘True’ or ‘Enabled’, the TCI state applied to receive the referenceCORESET is associated with the index of the reference signalstransmitted on the second serving cell and corresponding QCL types.Before the UE decodes the first PDCCH successfully, the UE assumes thatthe TCI state for receiving the first PDSCH is identical to the TCIstate applied for receiving the reference CORESET. Before the UE decodesthe second PDCCH successfully, the UE assumes that the TCI state forreceiving the second PDSCH is identical to the TCI state applied forreceiving the reference CORESET.

If the indicator indicates ‘0’ or ‘False or ‘Disabled’, at least the TCIstate applied to receive the reference CORESET is at least associatedwith the index of a first reference signal an index of a secondreference signal, and the corresponding QCL-types. The first referencesignal is transmitted on the first serving cell and the second referencesignal is transmitted on the second serving cell.

If the indicator indicates ‘0’ or ‘False or ‘Disabled’, before the UEdecodes the first PDCCH successfully, the UE assumes that the TCI statefor receiving the first PDSCH is identical to the TCI state applied forreceiving the reference CORESET; the UE refers to the index of the firstreference signal and corresponding QCL-type when interpreting the TCIstate; in one example, the UE receives the first PDSCH via a PDSCHantenna port quasi co-location derived from the index of the firstreference signal and the corresponding QCL-type in a TCI state appliedto receive the reference CORESET.

If the indicator indicates ‘0’ or ‘False or ‘Disabled’, before the UEdecodes the second PDCCH successfully, the UE assumes that the TCI statefor receiving the second PDSCH is identical to the TCI state applied toreceive the reference CORESET; the UE refers to the index of the secondreference signal and the corresponding QCL-type when interpreting theTCI state; in one example, the UE receives the second PDSCH via a PDSCHantenna port quasi co-location derived from the index of the secondreference signal and the corresponding QCL-type in a TCI state appliedto receive the reference CORESET.

In one exemplary embodiment, the opposite result from the value of theindicator is not precluded.

In one exemplary embodiment, the association between the TCI stateapplied to the reference CORESET and the first reference signal isconfigured in the configuration of the first serving cell, e.g., theconfiguration related to the cross carrier scheduling,CrossCarrierSchedulingConfig.

In one exemplary embodiment, the association between the TCI stateapplied to the reference CORESET and the first reference signal isconfigured in the configuration of the second serving cell, e.g., theCORESET configuration of the second serving cell.

In one exemplary embodiment, the UE may assume that the antenna ports ofone DM-RS port group of the first PDSCH are quasi co-located with theRS(s) in the RS set with respect to the QCL-type parameter(s) given bythe indicated TCI state if the time offset between the reception of theDL DCI of the first PDCCH and the first PDSCH is equal to or greaterthan a threshold, Threshold-Sched-Offset, wherein the threshold is basedon UE capability.

In one exemplary embodiment, in the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or not,according to the value of the indicator, and if the offset between thereception of the DL DCI of the second PDCCH and the second PDSCH is lessthan the threshold, Threshold-Sched-Offset, the UE may assume that theantenna ports of one DM-RS port group of the first PDSCH are quasico-located with the RS(s) in the RS set with respect to the QCL-typeparameter(s) used for the reference CORESET.

In one exemplary embodiment, in the cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, according to the value of the indicator, and if the offsetbetween the reception of the DL DCI of the first PDCCH and the firstPDSCH is less than the threshold, Threshold-Sched-Offset, the UE mayassume that the antenna ports of one DM-RS port group of the first PDSCHare quasi co-located with the first reference signal(s) in the RS setwith respect to the QCL-type parameter(s) used for the referenceCORESET.

In another embodiment, a UE is configured with a first serving cell anda second serving cell by the network. The control signal of the firstserving cell is transmitted on the second serving cell, e.g., PDCCHscheduling PDSCH. The downlink data transmission of the first servingcell is transmitted on the first serving cell. The UE receives ormonitors a first PDCCH transmitted on a scheduling CORESET of the secondserving cell. A first PDSCH is transmitted on the first serving cell. Inone embodiment, the first PDCCH may schedule the first PDSCH.

In one exemplary embodiment, the UE receives or monitors a second PDCCHtransmitted on the scheduling CORESET. A second PDSCH is transmitted onthe second serving cell. The second PDCCH may schedule the second PDSCH.

In one exemplary embodiment, the UE may be configured by a network aparameter indicating that the time offset between the reception of theDCI of the first PDCCH and the first PDSCH is possible to be less thanthe threshold value, Threshold-Sched-Offset.

In one exemplary embodiment, the UE may be configured by a network aparameter indicating that the time offset between the reception of theDCI of the first PDCCH and the first PDSCH is less than the thresholdvalue, Threshold-Sched-Offset.

In one exemplary embodiment, the UE may be configured by a network aparameter indicating that the time offset between the reception of theDCI of the first PDCCH and the first PDSCH is greater than or equal tothe threshold value, Threshold-Sched-Offset.

In one exemplary embodiment, the UE may be configured by a network aparameter indicating that the time offset between the reception of theDCI of the second PDCCH and the second PDSCH is possible to be less thanthe threshold value, Threshold-Sched-Offset.

In one exemplary embodiment, the UE may be configured by a network aparameter indicating that the time offset between the reception of theDCI of the second PDCCH and the second PDSCH is less than the thresholdvalue, Threshold-Sched-Offset.

Alternatively, the UE may be configured by a network parameterindicating that the time offset between the reception of the DCI of thesecond PDCCH and the second PDSCH is greater than or equal to thethreshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed embodiments, a reference CORESETis a CORESET with the lowest CORESET-ID in the latest slot in which oneor more CORESETs are configured for the UE.

In one or more of the above-disclosed embodiments, the reference CORESETis transmitted on the second serving cell.

In one or more of the above-disclosed embodiments, the reference CORESETis monitored by the UE on the second serving cell.

In one or more of the above-disclosed embodiments, the latest slot inwhich one or more CORESETs are configured for the UE means the latestslot with one or more CORESETs configured to be monitored by the UE.

In one or more of the above-disclosed embodiments, the reference CORESETis selected by finding the latest slot with one or more CORESETsconfigured to be monitored by the UE, and the reference CORESET is theCORESET with lowest CORESET-ID among those CORESETs monitored within thelatest slot.

In one or more of the above-disclosed embodiments, the reference CORESETmay be a CORESET configured for the second serving cell.

Additionally or alternatively, the reference CORESET may be a CORESETconfigured for the first serving cell.

Additionally or alternatively, the reference CORESET may be a CORESETwith the lowest CORESET-ID among the CORESETs configured for the firstserving cell and the CORESETs configured for the second serving cell.

In one or more of the above-disclosed embodiments, the UE may expect thetime offset between the reception of the DCI of the first PDCCH and thefirst PDSCH to be greater than or equal to a threshold.

In one or more of the above-disclosed embodiments, the UE may not expectthe time offset between the reception of the DCI of the first PDCCH andthe first PDSCH to be less than the threshold. This may mean that the UEdoes not receive and/or buffer the first PDSCH before the UEsuccessfully decodes the first PDCCH. Also, this may mean that the UEdoes not receive and/or buffer the first PDSCH if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than the threshold value, Threshold-Sched-Offset. This also maymean that the network prevents from or is not allowed to set orconfigure the time offset between reception of the DCI of the firstPDCCH and the first PDSCH to be less than a threshold value,Threshold-Sched-Offset. This also may mean that the network does nottransmit the first PDSCH if the time offset between the reception of theDCI of the first PDCCH and the first PDSCH is less than the thresholdvalue, Threshold-Sched-Offset.

Additionally or alternatively, for those cases whenTCI-PresentInDCI=‘Enabled’ and TCI-PresentInDCI=‘Disabled’ or notconfigured, the UE may not expect the time offset between the receptionof the DCI of the first PDCCH and the first PDSCH to be less than athreshold.

In one or more of the above-disclosed embodiments, the UE may receiveand/or buffer the second PDSCH via the TCI state used for the PDCCHquasi co-location indication of the reference CORESET, before the UEsuccessfully decodes the second PDCCH.

In one or more of the above-disclosed embodiments, the UE may receiveand/or buffer the second PDSCH via the TCI state used for PDCCH quasico-location indication of the reference CORESET, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than a threshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed embodiments, the network maytransmit the second PDSCH based on the TCI state used for the PDCCHquasi co-location indication of the reference CORESET, if the timeoffset between the reception of the DCI of the second PDCCH and thesecond PDSCH is less than a threshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed embodiments, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than the threshold, the UE does not receive and/or decode thefirst PDSCH or the remaining portion of the first PDSCH.

In one or more of the above-disclosed embodiments, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than the threshold, the UE discards the first PDSCH or theremaining portion of the first PDSCH.

In one or more of the above-disclosed embodiments, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than a threshold value, the UE detects or considers the firstPDCCH as an inconsistent control information.

In one or more of the above-disclosed embodiments, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than a threshold value, the UE does not transmit anacknowledgement signal, which corresponds to the first PDSCH, to thenetwork, e.g., ACK/NACK. This may mean that the network does not (expectto) receive an acknowledgement signal from the UE, wherein theacknowledgement signal corresponds to the first PDSCH, if the networktransmits the first PDSCH and the time offset between the reception ofthe DCI of the first PDCCH and the first PDSCH is less than thethreshold value, Threshold-Sched-Offset.

Notably, the above-disclosed embodiments can be applied to the caseswhen TCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ ornot configured. For example, for those cases whenTCI-PresentInDCI=‘Enabled’ and when TCI-PresentInDCI=‘Disabled’ or notconfigured, if the time offset between the reception of the DCI of thefirst PDCCH and the first PDSCH is less than a threshold value, the UEdoes not transmit an acknowledgement signal (e.g., ACK/NACK), whichcorresponds to the first PDSCH, to the network.

In one or more of the above-disclosed embodiments, the threshold valueis related to the time duration needed for the UE to successfully decodea PDCCH. Additionally, the threshold is related to UE capability.Additionally, the threshold can be Threshold-Sched-Offset.

In one or more of the above-disclosed embodiments, the UE may buffer aPDSCH if the time offset between the reception of PDSCH and thecorresponding scheduling DCI is less than the threshold value.

In one or more of the above-disclosed embodiments, the UE may buffer aPDSCH if the time offset between the reception of PDSCH and thecorresponding scheduling DCI is less than the threshold, which means theUE (will try to) receive the PDSCH before successfully decoding thecorresponding scheduling DCI.

In one or more of the above-disclosed embodiments, if the networkconfigures a CORESET configuration for a scheduled serving cell, the UEmay not use the parameter providing quasi co-location information forreceiving a PDCCH in the CORESETs of a scheduling serving cell.

In one or more of the above-disclosed embodiments, if the networkconfigures a CORESET configuration for a scheduled serving cell, the UEmay ignore the parameter providing the quasi co-location information forreceiving a PDCCH in the CORESETs of a scheduling serving cell.

In one or more of the above-disclosed embodiments, the network preventsfrom configuring a CORESET configuration for a scheduled serving cell.

In one or more of the above-disclosed embodiments, if the networkconfigures a CORESET configuration for a scheduled serving cell, theparameter providing the quasi co-location information for the receivingPDCCH is not allowed to be configured.

In one or more of the above-disclosed embodiments, if the networkconfigures a CORESET configuration for a scheduled serving cell, theparameter providing the quasi co-location information for the receivingPDCCH is ignored or not used when the PDCCH of the scheduled servingcell is transmitted on a scheduling serving cell.

According to one exemplary method, the UE receives or monitors a firstPDCCH transmitted on a scheduling CORESET of a second serving cell,wherein the first PDCCH schedules a first PDSCH transmitted on a firstserving cell; the UE receives the first PDSCH via the PDSCH antenna portquasi co-location derived from a default TCI state before the UE decodesthe first PDCCH successfully.

In another method, for those cases when TCI-PresentInDCI=‘Enabled’ andTCI-PresentInDCI=‘Disabled’, if the offset between the reception of theDL DCI of the first PDCCH and the first PDSCH is less than the thresholdThreshold-Sched-Offset, the UE may assume that the antenna ports of oneDM-RS port group of the first PDSCH are quasi co-located based on theTCI state used for the default state.

In one or more of the above-disclosed methods, the default TCI state isone of TCI states in the activated TCI states for receiving PDSCH in thefirst serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state mapped to one of codeponints in the TCI field for receivingPDSCH in the first serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state with the lowest TCI state ID in the activated TCI states forreceiving PDSCH in the first serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state with the lowest TCI state ID in the configured TCI statesfor receiving at least downlink transmission in the first serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state mapped to codepoint 0 in the TCI field for receiving PDSCHin the first serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state applied for receiving at least one of CORESETs configuredfor the first serving cell and/or the second serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state applied for receiving the CORESET with the lowest CORESET IDamong the CORESETs configured for the first serving cell and/or thesecond serving cell.

In one or more of the above-disclosed methods, the default TCI state isa TCI state applied for receiving the CORESET with the lowest CORESET IDamong the CORESETs configured for the first serving cell and/or thesecond serving cell.

According to another exemplary method, the UE receives or monitors afirst PDCCH transmitted on a scheduling CORESET of a second servingcell, wherein the first PDCCH schedules a first PDSCH transmitted on afirst serving cell; the UE assumes that the TCI state for the firstPDSCH is identical to a TCI state applied for receiving a referenceCORESET before the UE successfully decodes the first PDCCH; the UEreceives the first PDSCH via PDSCH antenna port quasi co-locationderived from the index of a first reference signal transmitted in thefirst serving cell and corresponding QCL type in a TCI state applied forreceiving the reference CORESET.

In another method, the reference CORESET is a CORESET configured for thesecond serving cell with the lowest CORESET-ID in the latest slot inwhich one or more CORESETs are configured for the UE.

In one or more of the above-disclosed methods, the UE refers to theindex of a first reference signal and the corresponding QCL type wheninterpreting a TCI state applied to the reference CORESET.

In one or more of the above-disclosed methods, the UE receives ormonitors a second PDCCH transmitted on the scheduling CORESET, whereinthe second PDCCH schedules a second PDSCH transmitted on the secondserving cell.

In one or more of the above-disclosed methods, before the UEsuccessfully decodes the second PDCCH, the UE assumes that the TCI statefor receiving the second PDSCH is identical to a TCI state applied tothe reference CORESET; and the UE refers to the index of a secondreference signal and the corresponding QCL-type when interpreting a TCIstate applied to the reference CORESET.

In one or more of the above-disclosed methods, a TCI state applied toreceiving the scheduling CORESET is at least associated with the indexof the first reference signals, the index of the second referencesignal, and the corresponding QCL types.

In one or more of the above-disclosed methods, the first referencesignal is transmitted on the first serving cell.

In one or more of the above-disclosed methods, the second referencesignal is transmitted on the second serving cell.

In one or more of the above-disclosed methods, the association between aTCI state applied to the reference CORESET and the first referencesignal is configured in the configuration of the first serving cell,e.g. the configuration related to cross carrier scheduling,CrossCarrierSchedulingConfig.

In one or more of the above-disclosed methods, the association between aTCI state applied to the reference CORESET and the first referencesignal is configured in the configuration of the second serving cell,e.g. CORESET configuration of the second serving cell.

According to another exemplary method, the UE receives or monitors afirst PDCCH transmitted on a scheduling CORESET of a second servingcell, wherein the first PDCCH schedules a first PDSCH transmitted on afirst serving cell; the UE assumes that the TCI state for the firstPDSCH is identical to a TCI state applied for receiving a referenceCORESET before the UE decodes the first PDCCH successfully, wherein theTCI state comprises index of a second reference signal transmitted onthe second serving cell; and the UE receives the first PDSCH via a PDSCHantenna port quasi co-location derived from the index of a firstreference signal transmitted in the first serving cell and thecorresponding QCL type.

In another method, the reference CORESET is a CORESET configured for thesecond serving cell with the lowest CORESET-ID in the latest slot inwhich one or more CORESETs are configured for the UE.

In another method, the association between the first reference signaland the second reference signal is explicitly configured to the UE.

In one or more of the above-disclosed methods, the association betweenthe first reference signal and the second reference signal is specifiedto the UE, e.g., specified in the specification.

In one or more of the above-disclosed methods, the association betweenthe first reference signal and the second reference signal is(implicitly) derived by the UE.

In one or more of the above-disclosed methods, the association betweenthe first reference signal and the second reference signal is(implicitly) derived by the UE via a rule, e.g. the index number of thefirst reference signal and the second reference signal.

According to another exemplary method, the UE receives or monitors afirst PDCCH transmitted on a scheduling CORESET of a second servingcell, wherein the first PDCCH schedules a first PDSCH transmitted on afirst serving cell; the UE determines a PDSCH antenna port quasico-location for receiving the first PDSCH based on an indicator beforethe UE successfully decodes the first PDCCH; and the UE receives thefirst PDSCH via PDSCH antenna port quasi co-location derived from adefault TCI state, wherein the default TCI state is based on the valueof the indicator.

In another method, if the indicator indicates ‘1’ or ‘True’ or‘Enabled’, the UE assumes that the default TCI state is identical to aTCI state applied to the reference CORESET.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, the default TCI state is a TCIstate mapped to one of codepoints in the TCI field for receiving PDSCHin the first serving cell.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, the default TCI state is a TCIstate with the lowest TCI state ID in the activated TCI states forreceiving PDSCH in the first serving cell.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, the default TCI state is a TCIstate mapped to codepoint 0 in the TCI field for receiving PDSCH in thefirst serving cell.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, the default TCI state is a TCIstate applied to receiving at least one of CORESETs configured for thefirst serving cell and/or the second serving cell.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, the default TCI state is a TCIstate applied to receiving the CORESET with the lowest CORESET ID amongthe CORESETs configured for the first serving cell and/or the secondserving cell.

In one or more of the above-disclosed methods, for those the cases whenTCI-PresentInDCI=‘Enabled’ and TCI-PresentInDCI=‘Disabled’, if theoffset between the reception of the DL DCI of the first PDCCH and thefirst PDSCH is less than Threshold-Sched-Offset, the UE may assume thatthe antenna ports of one DM-RS port group of the first PDSCH are quasico-located based on the default state.

In one or more of the above-disclosed methods, before the UEsuccessfully decodes the first PDCCH, the UE assumes the TCI state forreceiving the second PDSCH is identical to the TCI state applied to thereference CORESET.

According to another exemplary method, the UE receives or monitors afirst PDCCH transmitted on a scheduling CORESET of a second servingcell, wherein the first PDCCH schedules a first PDSCH transmitted on afirst serving cell; the UE assumes that the TCI state for receiving thefirst PDSCH is identical to a TCI state applied for the referenceCORESET before the UE successfully decodes the first PDCCH, wherein theTCI state applied to receiving the reference CORESET is at leastassociated with the index of a first reference signals, the index of asecond reference signal, and the corresponding QCL types; and the UEreceives the first PDSCH via a PDSCH antenna port quasi co-locationderived from the index of a first reference signal and the correspondingQCL type based on the value of the indicator.

In another method, the reference CORESET is a CORESET configured for thesecond serving cell with the lowest CORESET-ID in the latest slot inwhich one or more CORESETs are configured for the UE.

In one or more of the above-disclosed methods, the UE receives ormonitors a second PDCCH transmitted on the scheduling CORESET, whereinthe second PDCCH schedules a second PDSCH transmitted on the secondserving cell.

In one or more of the above-disclosed methods, the UE interprets the TCIstate applied to the reference CORESET based on an indicator.

In one or more of the above-disclosed methods, the first referencesignal is transmitted on the first serving cell.

In one or more of the above-disclosed methods, the second referencesignal is transmitted on the second serving cell.

In one or more of the above-disclosed methods, the association betweenthe TCI state applied to the reference CORESET and the first referencesignal is configured in the configuration of the first serving cell,e.g. configuration related to cross carrier scheduling,CrossCarrierSchedulingConfig.

In one or more of the above-disclosed methods, the association betweenthe TCI state applied for the reference CORESET and the first referencesignal is configured in the configuration of the second serving cell,e.g. CORESET configuration of the second serving cell.

In one or more of the above-disclosed methods, if the indicatorindicates ‘1’ or ‘True’ or ‘Enabled’, the UE refers to the index of thefirst reference signal and the corresponding QCL type when interpretingthe TCI state applied to the reference CORESET.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, the UE refers to the index ofthe first reference signal and the corresponding QCL type wheninterpreting the TCI state applied to the reference CORESET.

In one or more of the above-disclosed methods, before the UEsuccessfully decodes the second PDCCH, the UE assumes that the TCI statefor receiving the second PDSCH is identical to a TCI state applied tothe reference CORESET; and the UE refers to the index of the secondreference signal and QCL type when interpreting a TCI state applied tothe reference CORESET regardless of the value of the indicator.

In another method, if the indicator indicates ‘1’ or ‘True’ or‘Enabled’, the TCI state applied to receiving the reference CORESET isassociated with the index of reference signals transmitted on the secondserving cell and the corresponding QCL types.

In another method, if the indicator indicates ‘0’ or ‘False’ or‘Disabled’, the TCI state applied to receiving the reference CORESET isat least associated with the index of a first reference signals, theindex of a second reference signal, and the corresponding QCL types.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, and before the UE successfullydecodes the first PDCCH, the UE receives the first PDSCH via a PDSCHantenna port quasi co-location derived from the index of the firstreference signal and the corresponding QCL type in a TCI state appliedto receiving the reference CORESET.

In one or more of the above-disclosed methods, if the indicatorindicates ‘0’ or ‘False’ or ‘Disabled’, and before the UE successfullydecodes the second PDCCH, the UE receives the second PDSCH via a PDSCHantenna port quasi co-location derived from the index of the secondreference signal and the corresponding QCL type in a TCI state appliedto receiving the reference CORESET.

According to another exemplary method, the UE receives or monitors afirst PDCCH transmitted on a scheduling CORESET of a second servingcell, wherein the first PDCCH schedules a first PDSCH transmitted on afirst serving cell; the UE discards the first PDSCH or the remainingportion of the first PDSCH if the time offset between the reception ofthe DCI of the first PDCCH and the first PDSCH is less than a threshold.

In another method, if the time offset between the reception of the DCIof the first PDCCH and the first PDSCH is less than the threshold, theUE does not receive and/or decode the first PDSCH or the remainingportion of the first PDSCH.

In one or more of the above-disclosed methods, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than the threshold, the UE detects or considers the first PDCCHis an inconsistent control information.

In one or more of the above-disclosed methods, if the time offsetbetween the reception of the DCI of the first PDCCH and the first PDSCHis less than the threshold, the UE does not transmit an acknowledgementsignal, which corresponds to the first PDSCH, to network, e.g. ACK/NACK.

In one or more of the above-disclosed methods, the threshold is relatedto the time duration needed for the UE to successfully decode a PDCCH.

In one or more of the above-disclosed methods, the threshold is relatedto UE capability.

In one or more of the above-disclosed methods, the threshold can beThreshold-Sched-Offset.

FIG. 6 is a flow chart 600 according to one exemplary embodiment fromthe perspective of a UE. In step 605, the UE receives a configuration ofa first serving cell and a second serving cell from a network. In step610, the UE receives and/or monitors a first PDCCH transmitted on ascheduling CORESET of the second serving cell, wherein the first PDCCHschedules a first PDSCH transmitted on the first serving cell. In step615, the UE receives and/or monitors a second PDCCH transmitted on ascheduling CORESET of the second serving cell, wherein the second PDCCHschedules a second PDSCH transmitted on the second serving cell. In step620, the UE receives and/or buffers the second PDSCH via the TCI stateused for PDCCH quasi co-location indication of the CORESET with thelowest CORESET-ID in the latest slot in which one or more CORESETs areconfigured for the UE, before the UE decodes successfully the secondPDCCH. In step 625, the UE does not receive and/or buffer the firstPDSCH before the UE decodes successfully the first PDCCH, i.e. the UEdecodes successfully the first PDCCH before the UE receives and/orbuffers the first PDSCH.

In one embodiment, the UE is configured a first serving cell and asecond serving cell by a network.

In another method, the UE is configured with a parameter indicating thatthe time offset between the reception of the DCI of the first PDCCH andthe first PDSCH may be less than the threshold value,Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the UE is configured witha parameter indicating that the time offset between the reception of theDCI of the second PDCCH and the second PDSCH is possible to be less thanthe threshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the UE expects the timeoffset between the reception of the DCI of the first PDCCH and the firstPDSCH is greater than or equal to a threshold value,Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the threshold value,Threshold-Sched-Offset, is related to the UE capability and/or the timeduration needed for the UE to successfully decode a PDCCH.

In one or more of the above-disclosed methods, the UE does not receiveand/or buffer the first PDSCH if the time offset between the receptionof the DCI of the first PDCCH and the first PDSCH is less than thethreshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, if the time offsetbetween the reception of the DCI of the second PDCCH and the secondPDSCH is less than a threshold value, Threshold-Sched-Offset, the UEreceives and/or buffers the second PDSCH via the TCI state used for thePDCCH quasi co-location indication of the CORESET with the lowestCORESET-ID in the latest slot in which one or more CORESETs areconfigured for the UE.

In one or more of the above-disclosed methods, if the network configuresa CORESET configuration for a scheduled serving cell, the UE does notuse the parameter providing the quasi co-location information forreceiving the PDCCH in the CORESETs of a scheduling serving cell.

In one or more of the above-disclosed methods, if the network configuresa CORESET configuration for the scheduled serving cell, the UE ignoresthe parameter providing the quasi co-location information for receivingthe PDCCH in the CORESETs of a scheduling serving cell.

FIG. 7 is a flow chart 700 according to one exemplary embodiment fromthe perspective of a network. In step 705, the network configures afirst serving cell and a second serving cell to a UE. In step 710, thenetwork transmits a second PDCCH to the UE via a scheduling CORESET ofthe second serving cell, wherein the second PDCCH schedules a secondPDSCH transmitted on the second serving cell, and a time offset betweenreception of the DCI of the second PDCCH and the second PDSCH may beless than a threshold value, Threshold-Sched-Offset. In step 715, thenetwork transmits a first PDCCH to the UE via a scheduling CORESET ofthe second serving cell, wherein the first PDCCH schedules a first PDSCHtransmitted on the first serving cell. In step 720, the network preventsfrom setting or configuring the time offset between reception of the DCIof the first PDCCH and the first PDSCH to be less than a thresholdvalue, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the network is notallowed to set or configure the time offset between reception of the DCIof the first PDCCH and the first PDSCH is less than the threshold value,Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the network configures tothe UE a parameter indicating that the time offset between the receptionof the DCI of the first PDCCH and the first PDSCH is greater than orequal to the threshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the network configures tothe UE a parameter indicating that the time offset between the receptionof the DCI of the second PDCCH and the second PDSCH may be less than thethreshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the threshold value,Threshold-Sched-Offset, is related to UE capability and/or the timeduration needed for the UE to decode a PDCCH successfully.

In one or more of the above-disclosed methods, the network does nottransmit the first PDSCH if the time offset between the reception of theDCI of the first PDCCH and the first PDSCH is less than the thresholdvalue, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the network transmits thesecond PDSCH based on the TCI state used for the PDCCH quasi co-locationindication of the CORESET with the lowest CORESET-ID in the latest slotin which one or more CORESETs are configured for the UE, if the timeoffset between the reception of the DCI of the second PDCCH and thesecond PDSCH is less than a threshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the network does notreceive an acknowledgement signal from the UE, wherein theacknowledgement signal corresponds to the first PDSCH, if the networktransmits the first PDSCH and the time offset between the reception ofthe DCI of the first PDCCH and the first PDSCH is less than thethreshold value, Threshold-Sched-Offset.

In one or more of the above-disclosed methods, the network prevents fromconfiguring a CORESET configuration for a scheduled serving cell.

In one or more of the above-disclosed methods, if the network configuresa CORESET configuration for a scheduled serving cell, a parameterproviding the quasi co-location information for receiving PDCCH is notallowed to be configured.

In one or more of the above-disclosed methods, if the network configuresa CORESET configuration for a scheduled serving cell, a parameterproviding the quasi co-location information for receiving PDCCH isignored or not used when PDCCH of the scheduled serving cell istransmitted on a scheduling serving cell.

As those skilled in the art will appreciate, the various disclosedembodiments may be combined to form new embodiments and/or methods.

Referring back to FIGS. 3 and 4, in one embodiment, the device 300includes a program code 312 stored in memory 310. The CPU 308 couldexecute program code 312 to (i) receive a configuration of a firstserving cell and a second serving cell from a network, (ii) receiveand/or monitor a first PDCCH transmitted on a scheduling CORESET of thesecond serving cell, wherein the first PDCCH schedules a first PDSCHtransmitted on the first serving cell, (iii) receive and/or monitor asecond PDCCH transmitted on a scheduling CORESET of the second servingcell, wherein the second PDCCH schedules a second PDSCH transmitted onthe second serving cell, (iv) receive and/or buffer the second PDSCH viathe TCI state used for PDCCH quasi co-location indication of the CORESETwith the lowest CORESET-ID in the latest slot in which one or moreCORESETs are configured for the UE, before the UE decodes successfullythe second PDCCH, and (v) to not receive and/or buffer the first PDSCHbefore the UE decodes successfully the first PDCCH.

In another embodiment, the device includes a program code 312 stored inthe memory 310. The CPU 308 could execute program code 312 to (i)configure a first serving cell and a second serving cell to a UE, (ii)transmit a second PDCCH to the UE via a scheduling CORESET of the secondserving cell, wherein the second PDCCH schedules a second PDSCHtransmitted on the second serving cell, and the time offset betweenreception of the DCI of the second PDCCH and the second PDSCH may beless than a threshold value, Threshold-Sched-Offset, (iii) transmit afirst PDCCH to the UE via a scheduling CORESET of the second servingcell, wherein the first PDCCH schedules a first PDSCH transmitted on thefirst serving cell, (iv) prevent from setting or configuring the timeoffset between reception of the DCI of the first PDCCH and the firstPDSCH to be less than a threshold value, Threshold-Sched-Offset.

Furthermore, the CPU 308 can execute the program code 312 to perform allof the above-described actions and steps or others methods describedherein.

The above-disclosed methods assists in avoiding ambiguity of beam usageindication during downlink data buffering considering cross carrierscheduling.

Various aspects of the disclosure have been described above. It shouldbe apparent that the teachings herein may be embodied in a wide varietyof forms and that any specific structure, function, or both beingdisclosed herein is merely representative. Based on the teachings hereinone skilled in the art should appreciate that an aspect disclosed hereinmay be implemented independently of any other aspects and that two ormore of these aspects may be combined in various ways. For example, anapparatus may be implemented or a method may be practiced using anynumber of the aspects set forth herein. In addition, such an apparatusmay be implemented or such a method may be practiced using otherstructure, functionality, or structure and functionality in addition toor other than one or more of the aspects set forth herein. As an exampleof some of the above concepts, in some aspects concurrent channels maybe established based on pulse repetition frequencies. In some aspectsconcurrent channels may be established based on pulse position oroffsets. In some aspects concurrent channels may be established based ontime hopping sequences.

Those of skill in the art would understand that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Those of skill would further appreciate that the various illustrativelogical blocks, modules, processors, means, circuits, and algorithmsteps described in connection with the aspects disclosed herein may beimplemented as electronic hardware (e.g., a digital implementation, ananalog implementation, or a combination of the two, which may bedesigned using source coding or some other technique), various forms ofprogram or design code incorporating instructions (which may be referredto herein, for convenience, as “software” or a “software module”), orcombinations of both. To clearly illustrate this interchangeability ofhardware and software, various illustrative components, blocks, modules,circuits, and steps have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. Skilled artisans mayimplement the described functionality in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the presentdisclosure.

In addition, the various illustrative logical blocks, modules, andcircuits described in connection with the aspects disclosed herein maybe implemented within or performed by an integrated circuit (“IC”), anaccess terminal, or an access point. The IC may comprise a generalpurpose processor, a digital signal processor (DSP), an applicationspecific integrated circuit (ASIC), a field programmable gate array(FPGA) or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, electrical components, opticalcomponents, mechanical components, or any combination thereof designedto perform the functions described herein, and may execute codes orinstructions that reside within the IC, outside of the IC, or both. Ageneral purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

It is understood that any specific order or hierarchy of steps in anydisclosed process is an example of a sample approach. Based upon designpreferences, it is understood that the specific order or hierarchy ofsteps in the processes may be rearranged while remaining within thescope of the present disclosure. The accompanying method claims presentelements of the various steps in a sample order, and are not meant to belimited to the specific order or hierarchy presented.

The steps of a method or algorithm described in connection with theaspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module (e.g., including executable instructions and relateddata) and other data may reside in a data memory such as RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a harddisk, a removable disk, a CD-ROM, or any other form of computer-readablestorage medium known in the art. A sample storage medium may be coupledto a machine such as, for example, a computer/processor (which may bereferred to herein, for convenience, as a “processor”) such theprocessor can read information (e.g., code) from and write informationto the storage medium. A sample storage medium may be integral to theprocessor. The processor and the storage medium may reside in an ASIC.The ASIC may reside in user equipment. In the alternative, the processorand the storage medium may reside as discrete components in userequipment. Moreover, in some aspects any suitable computer-programproduct may comprise a computer-readable medium comprising codesrelating to one or more of the aspects of the disclosure. In someaspects a computer program product may comprise packaging materials.

While the invention has been described in connection with variousaspects, it will be understood that the invention is capable of furthermodifications. This application is intended to cover any variations,uses or adaptation of the invention following, in general, theprinciples of the invention, and including such departures from thepresent disclosure as come within the known and customary practicewithin the art to which the invention pertains.

What is claimed is:
 1. A method of a User Equipment (UE), the methodcomprising: receiving a configuration of a first serving cell and asecond serving cell from a network; receiving and/or monitoring a firstPhysical Downlink Control Channel (PDCCH) transmitted on the secondserving cell, wherein the first PDCCH schedules a first PhysicalDownlink Shared Channel (PDSCH) transmitted on the first serving cell;receiving and/or monitoring a second PDCCH transmitted on the secondserving cell, wherein the second PDCCH schedules a second PDSCHtransmitted on the second serving cell; receiving and/or buffering thesecond PDSCH based on a first Transmission Configuration Indication(TCI) state used for PDCCH quasi co-location indication of a referenceControl Resource Set (CORESET) if a time offset between reception ofDownlink Control Information (DCI) of the second PDCCH and the secondPDSCH is less than a threshold; and receiving and/or buffering the firstPDSCH based on a second TCI state, wherein the second TCI statecomprises the lowest TCI state ID (Identity) in activated TCI states forreceiving PDSCH in the first serving cell, if a time offset betweenreception of DCI of the first PDCCH and the first PDSCH is less than thethreshold.
 2. The method of claim 1, wherein the reference CORESET is aCORESET with lowest CORESET-ID among those CORESETs monitored within thelatest slot.
 3. The method of claim 1, wherein the threshold is relatedto UE capability or the time duration needed for the UE to successfullydecode the PDCCH.
 4. The method of claim 1, further comprising:receiving and/or buffering the second PDSCH based on the first TCI statebefore the UE decodes successfully the second PDCCH.
 5. The method ofclaim 1, further comprising: receiving and/or buffering the first PDSCHbased on the second TCI state before the UE decodes successfully thefirst PDCCH.
 6. The method of claim 1, wherein the first serving cell isa scheduled serving cell and the second serving cell is a schedulingserving cell.
 7. A method for a network, the method comprising:configuring a first serving cell and a second serving cell to a UserEquipment (UE); transmitting a second Physical Downlink Control Channel(PDCCH) to the UE on the second serving cell, wherein the second PDCCHschedules a second Physical Downlink Shared Channel (PDSCH) transmittedon the second serving cell; transmitting a first PDCCH to the UE on thesecond serving cell, wherein the first PDCCH schedules a first PDSCHtransmitted on the first serving cell; transmitting the second PDSCHbased on a first Transmission Configuration Indication (TCI) state usedfor PDCCH quasi co-location indication of a reference Control ResourceSet (CORESET), if a time offset between reception of Downlink ControlInformation (DCI) of the second PDCCH and the second PDSCH is less thana threshold; and transmitting the second PDSCH based on a second TCIstate, wherein the second TCI state comprises the lowest TCI state ID(Identity) in activated TCI states for receiving PDSCH in the firstserving cell, if a time offset between reception of DCI of the firstPDCCH and the first PDSCH is less than the threshold.
 8. The method ofclaim 7, wherein the reference CORESET is a CORESET with lowestCORESET-ID among those CORESETs monitored within the latest slot.
 9. Themethod of claim 7, wherein the threshold is related to UE capability orthe time duration needed for the UE to successfully decode the PDCCH.10. The method of claim 7, wherein the first serving cell is a scheduledserving cell and the second serving cell is a scheduling serving cell.11. A network, comprising: a processor; a memory operatively coupled tothe processor, wherein the processor is configured to execute a programcode to: configure a first serving cell and a second serving cell to aUser Equipment (UE); transmit a second Physical Downlink Control Channel(PDCCH) to the UE on the second serving cell, wherein the second PDCCHschedules a second Physical Downlink Shared Channel (PDSCH) transmittedon the second serving cell; transmit a first PDCCH to the UE on thesecond serving cell, wherein the first PDCCH schedules a first PDSCHtransmitted on the first serving cell; transmit the second PDSCH basedon a first Transmission Configuration Indication (TCI) state used forPDCCH quasi co-location indication of a reference Control Resource Set(CORESET), if a time offset between reception of Downlink ControlInformation (DCI) of the second PDCCH and the second PDSCH is less thana threshold; and transmit the second PDSCH based on a second TCI state,wherein the second TCI state comprises the lowest TCI state ID(Identity) in activated TCI states for receiving PDSCH in the firstserving cell, if a time offset between reception of DCI of the firstPDCCH and the first PDSCH is less than the threshold.
 12. The network ofclaim 11, wherein the reference CORESET is a CORESET with lowestCORESET-ID among those CORESETs monitored within the latest slot. 13.The network of claim 11, wherein the threshold is related to UEcapability or the time duration needed for the UE to successfully decodethe PDCCH.
 14. The network of claim 11, wherein the first serving cellis a scheduled serving cell and the second serving cell is a schedulingserving cell.